{"id":"USN-7955-2","summary":"python-urllib3 regression","details":"USN-7955-1 fixed vulnerabilities in urllib3. The update introduced a\nregression in response streaming on Ubuntu 20.04 LTS and Ubuntu 22.04 LTS.\nThis update fixes the problem.\n\nWe apologize for the inconvenience.\n\nOriginal advisory details:\n\n It was discovered that urllib3 incorrectly handled decompression during\n HTTP redirects. An attacker could possibly use this issue to cause urllib3\n to use excessive resources, causing a denial of service.","modified":"2026-02-10T04:50:47Z","published":"2026-01-19T11:57:37Z","related":["UBUNTU-CVE-2026-21441"],"upstream":["CVE-2026-21441","UBUNTU-CVE-2026-21441"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-7955-2"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-21441"},{"type":"REPORT","url":"https://bugs.launchpad.net/bugs/2138420"}],"affected":[{"package":{"name":"python-urllib3","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/python-urllib3@1.25.8-2ubuntu0.4+esm4?arch=source&distro=esm-infra/focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.25.8-2ubuntu0.4+esm4"}]}],"versions":["1.24.1-1ubuntu1","1.24.1-1ubuntu2","1.25.8-1","1.25.8-2","1.25.8-2ubuntu0.1","1.25.8-2ubuntu0.2","1.25.8-2ubuntu0.3","1.25.8-2ubuntu0.4","1.25.8-2ubuntu0.4+esm1","1.25.8-2ubuntu0.4+esm2","1.25.8-2ubuntu0.4+esm3"],"ecosystem_specific":{"binaries":[{"binary_version":"1.25.8-2ubuntu0.4+esm4","binary_name":"python3-urllib3"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"},"database_specific":{"cves_map":{"cves":[{"id":"CVE-2026-21441","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}],"ecosystem":"Ubuntu:Pro:20.04:LTS"},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-7955-2.json"}},{"package":{"name":"python-urllib3","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/python-urllib3@1.26.5-1~exp1ubuntu0.6?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.26.5-1~exp1ubuntu0.6"}]}],"versions":["1.26.5-1~exp1","1.26.5-1~exp1ubuntu0.1","1.26.5-1~exp1ubuntu0.2","1.26.5-1~exp1ubuntu0.3","1.26.5-1~exp1ubuntu0.4","1.26.5-1~exp1ubuntu0.5"],"ecosystem_specific":{"binaries":[{"binary_version":"1.26.5-1~exp1ubuntu0.6","binary_name":"python3-urllib3"}],"availability":"No subscription required"},"database_specific":{"cves_map":{"cves":[{"id":"CVE-2026-21441","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}],"ecosystem":"Ubuntu:22.04:LTS"},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-7955-2.json"}}],"schema_version":"1.7.3"}